If accidental system discharge occurs, ventilate work area before resuming service.
Additional health and safety information may be obtained from the refrigerant and lubricant manufacturers.
- When an A/C System has been opened to the atmosphere, such as during installation or repair, it must be evacuated using a R-134a refrigerant recover/recycling/charging station (If the system has been open for several days, the receiver/dryer should be replaced, and the system should be evacuated for several hours.)
- Connect a R-134a refrigerant recovery/recycling/charging station (A) to the high-pressure service port (B) and the low-pressure service port (C), following the equipment manufacturer's instruction. Evacuate the system.
- Connect high charging hose (1) and low charging hose (2) of manifold gauge set (3) respectively as follows: High charging hose (1) - High pressure charging valve (4) on condenser outlet pipe Low charging hose (2) - Low pressure charging valve (5) on suction pipe
- Attach center charging hose (6) of manifold gauge set (3) to vacuum pump (7).
- Operate vacuum pump (7), and then open discharge side valve (Hi) (8) of manifold gauge set (3). If there is no blockage in the system, there will be an indication on high pressure gauge (9). In this case, open the other side valve (Lo) (10) of the set and repair the system.
Approximately 10 minutes later, low pressure gauge (11) should indicate - 14.7 psi (100 kPa) providing no leakage exists.
NOTEIf the system does not indicate - 14.7 psi (100 kPa), close both valves, stop vacuum pump and watch movement of low pressure gauge.
Increase in the gauge reading suggests existence of leakage. In this case, repair the system before continuing its evacuation.
- Evacuation should be carried out for at least 15 minutes.
Continue evacuation until low pressure gauge (11) indicates - 14.7 psi (100 kPa), and then close both valves (8), (10). 7)Stop vacuum pump (7), and then disconnect center charging hose (6) from pump inlet. Now, the system is ready for charging refrigerant.